Epirur_Cattle: A Spatially Explicit Agent-based Simulator of Beef Cattle Movements

We present Epirur_Cattle, a spatially explicit agent-based simulator for synthesizing beef cattle movements and forecasting zoonotic disease spread in the American beef cattle industry. Farm, ranch, and feedlot operators make decisions on cattle trades according to cattle weights and market conditions. Contact networks of cattle are generated by geographical proximity and disease is spread through a simple compartmental model on the dynamic contact structures. An analysis of the network metrics of the contact networks and the aggregated contact networks provides insight into the influence of the network dynamics on the epidemic dynamics. Using farm data based on the Kansas cattle industry, our experiments show a tri-modal distribution of total case counts that becomes bi-modal for weaker diseases. These results are explained by the interaction of the disease and trading processes. We show how simple network metrics, such as the average node degree, can track the complex trading processes which shape the evolution of the disease at an agent level.